Method and apparatus for the fixation of nitrogen



Feb. 27, 1923.

C. H. BUETTNER METHOD AND APPARATUS FOR THE FIXATION OF NITROGEN 3, 1922 2 sheets-sheet 2 Filed Feb.

I O 1 1 Q o 1 1 3 Patented Feb. 27, 1923.

STATES- PATENT GFF CHAR-LES H. BUETTNER. OF CINCINNATI, OHIO.

Application filed February 3, 1922.

To all. whom. it may concern.

lie it known that l.(n.\u1.| ;s ll.lli'i-:'1"r.\'1-:u. a citizen of the United States. residing at Cincinnati. in the county of llamilton and State of Ohio, have invented certain new and useful Improvements in Methods and .ip 'iaratus for the Fixation of Nitrogen, of which the following is a specification.

My invention relates to improvements in method and means for the fixation of nitrogen from the atmosphere. ()ne of its objects is to provide a more simple ellicient and reliable method for the fixation of nitrogen from the atmosphere either in a relatively large or relatively small installation unit. Another object is to provide an improved method adapted to produce fixed nitrogen as nitric acid as well as in the form of salts of nitric acid. An-

other object is to provide improved simple and reliable apparatus to carry out my improved method. Another object is to provide an improved arrangen'ient of current fiow and air circulation relative thereto. Another object is to provide improved means to establish orreestablish the current flow and to observe the current flow through the atmosphere. and to regulate the atmospheric flow. My invention also comprises certain details of form combination, arrangement and order of procedure, all ofwhich will be fully set forth in the description of the ac companying drawings in which;

Fig. 1. is a diagrammatic vertical section through apparatus embodying my improvements and adapted to carry out my improved method of operation.

Fig. '2 is a side elevation of one of the units employed to.maintain a suitable electrical flow and atmospheric flow for the continuous'fixation of nitrogen.

Fig. 3 is a vertical section through the same taken on line 3-3' of Fig. 2, and showing a different position of the parts.

Fig. 4 is a horizontal section through the same taken on line l4 of Fig. 2.v

Fig. 5 is an enlarged sectional detail taken on line of Fig. 2.

The accompanylng drawings illustrate the chamber is a bushing 29 into which 1S preferred embodiment of my improved apparatus and one eminently suited to thecarrying out of my improved method.

In said apparatus 15 represents a storage reservoir for the storage of water or an alkaline solution, as for instance lime-water or Serial No. 533,802.

a water solution of soda or potash. A. valve controlled conduit 16 leads a regulated quantity of liquid from the reservoir 15 to one or more scrubbers or absorbers 17 where the liquid is discharged over a bed of coke, gravel or other chemically inert substance 18 where-- by a large liquid surface is exposed to the gaseous contents of the scrubber to facilitate absorption of the nitrogen fixation products into the liquid to form more or less concentrated solution of the gaseous fixation products in the liquid. \Vhen the liquid in the scrubber has become saturated with the nitrogen fixation products it isallowed to flow downwardly through the conduits 1!) and 20 into a rich liquor storage reservoir 21 from which the rich liquor may be continuously or intermittently withdrawn through a conduit 21 to be used directly or to be further concentrated and refined. \Vhere water only is supplied to the scrubber the rich liquor will consist of a more or less concentrated solution of nitric and nitrous acids which may be refined and concentrated to a cou'miercial or concentrated nitric acid. \Vhere an alkaline liquid is supplied to the scrubber the rich liquor will consist of a more or less concentrated solution of alkaline nitrate and nitrite. which may be used directly for fertilizer purposes, or may be concentrated if desired.

In order to effect the fixation of nitrogen.

I preferably employ a series of chambers 22 and conduits or flues 24 in which the fixation takes place and from which the fixation products are conductedto one or more scrubbers 17 where-the nitrogen fixation products are absorbed or extracted. The chambers 22 and flues 24 are preferably built up from ordinary iron pipe fittings in which the chambers 22 are formed from tees or crosses 25 preferably fitted with bushings 26 at their upper ends. which bushings are provided preferably with downwardly directed annular beads 27 which each constitute one of the electrical terminals for a high tension circuit 49 to form a spark or flaming are through the gases within the chamber 22. At the lower end of each threaded a metal sleeve 30 within which is rigidlysecured a relativelythick sleeve 31 of insulating material such as hard rubber or porcelain for instance. A thin metallic. sleeve 32 is preferably rigidly secured within the insulating sleeve 31 and a stem or elec-' trode 33 of carbon metal or other electrical conducting material is mounted within the sleeve 32 to move endwise therein. A cap 34 of carbon metal or other electrical conducting material of a relatively chemically inert nature is preferably detachably and renewably attached to the inner end of the stem 33, and said cap 34 or the inner end of the stem 33 is adapted when the stem 33 is pushed upwardly within the sleeve 32 to contact with the bead 27 or bushing 26 to establish an annular arc or train of sparks between the stem 33 and bushing 26 or bead 27 through the gaseous contents of the chamber 22. As soon as contact has been established between the stem 33 and bushing 26. the stem 33 is allowed to gravitate through the sleeve 32 to elongate the arc or train of sparks until the stem reaches the lower limit of its movement An insulated head or push button 33 at the lower end of each stem 33 enables said stem to be pushed upwardly by hand whenever necessary to reestablish an arc. At one side of the chamber is a bushing 36 provided with a transparent section or window 37 which enables. the are or spark-s within the respective chambers 22 to'be observed. At the opposite side of each chamber 22 is a bushing 38 to which is at-,

tached an air supply conduit 39 which is provided with a regulating valve 40 to enable the amount of air admitted to eachc chamber 22 to be accurately regulated. The air from the conduit 39 enters the respective chambers 22 and the annular arcs or trains of sparks form in each chamber 22 a relatively thin but extensive annular scicen or zone through 'which the air entering the chamber 22 is forced to pass to reach one of the ofl'take conduits or flues 24. The air current is thus caused to pass through the annular electrically heated and chemically active screen or zone where it is for an instant highly heated and then quickly carried past the heating zone into a cooler space or zone and thence through the conduit or flue 24 to a scrubber 17. The amount of heat imparted to and remaining with the gases in passing through the arc zone is sufiicient to provide an automatic and steady flow of gases through the arc zone and on through the fines to the scrubber without requiring any special or power driven system of gas circulation, w ich is an important advantage where a small and simple installation is desired. 1 preferably provide a gas exit conduit 42 provided with regulating valves 43, whereby a regulated amount of gas from which the fixation products have been extracted may be escaped and wasted if desired and also a valve controlled branch 44 leading to a secondary scrubber 45, through which the gases from scrubber 17 may be forced by a flower or pump 46, and wasted from the exit conduit 47, or further treated in a scrubber not shown containing an alkaline solution if dcsired. In practice the gases absorbed in the scrubbers and a small escape of gases at the lower end of the conduit 20 or through the waste conduit 42 provides for a substantially continuous and uniform feed of air to the chambers 22 and then to the scrubbers 17.

I preferably employ a separate high ten sion transformer for each arc or unit. comprising a primary coil 45 included in an alternating current service line 46, and a secondary coil 47 connected at one end by a line wire 48 to the stem 33 or preferably to the sleeve 32 while the opposite end of the coil is connected to the bushing 26 of the same chamber or unit by a line wire -19.

My improved method and apparatus provides for a simple and reliable system of operation and apparatus therefore in which the operation of each unit is under observation and control. and insures practically all of the air being subjected to the action of the current in such manner as to attain the most suitable and eflicient results.

The method and apparatus herein shown and described is capable of considerable modification without departing from the spirit of my invention.

What I claim is g 1. The method of nitrogen fixation which comprises feeding a current of mixed oxygh and nitrogen gas by convection through 'aflue and through a zone of substantially continuous electrical flaming arc interposed in said'flue to an absorbing element which serves to absorb and segregatethe fixation products.

2. A nitrogen fixation apparatus comprising an absorbing element to absorb and segregate the fixation products, a gas flue lead ing to said absorbing element, a fixation chamber in said flue, means to maintain a zone of substantially continuous flaming arc electrical discharge across the path of a gaseous current flowing through said fixation chamber, the heat supplied by said electrical discharge serving to automatically maintain a flow of gases through said chamber and flue to said absorbing element.

3. A nitrogen fixation apparatus comprising an absorbing element, a gas flue leading to said absorbing element, a fixation chamber in said flue, a stationarily mounted electrode in the upper portion of said chamber. and an electrode in the lower portion of said chamber movable to and from said stationarily mounted electrode to establish an arc. electrical discharge in said chamber and to extend said are discharge to form a zone of electrical discharge through which a gaseous current in said chamber and fiue is required to pass.

4. A nitrogen fixation apparatus co1npris.-

,ng a conduit through which a flow of gas .s adapted to be maintained, an annular zlectrode encircling a section of said conluit, an electrode movable to and from said annular electrode and insulated ,therefrom iorestablish and maintain an annular elec- :rical are within said conduit and forming 1- zone within said conduit through which the current of gas in said conduit is required to flow.

5. A nitrogen fixation apparatus comprising a conduit through which an upwardly directed flow of gas is adapted to be maintained, an annular electrode encircling a section of said "conduit, an electrode located substantiallyconcentrically beneath said annular electrode and movable to and from said annular electrode and insulatedtherefrom to establish and maintain an elongated annular; electrical arc within said conduit and forming a tubular zone within said conduit through which the current of gas in said conduit is required to flow.

6. A nitrogen fixation apparatus comprising aconduit through which an upwardly directed flow of gas is adapted to be maintained, an annular electrode encircling a section of said conduit, an electrodelocated substantially concentrically beneath said annular electrode and movable to and from said annular electrode and insulated therefrom to establish and maintain an elongated annular'zone of elect'ricaldischarge within said conduit and forming a tubular zone through which the current of gas in said conduit is required to flow.

7. A nitrogen fixation apparatus comprising an absorption element, a conduit through which a flow of gas to said absorbing element is adapted to be maintained and having a plurality of gas intake ports, an annular electrode for each of said intake ports. an electrode independently movable to and from each of said annular electrodes and insulated therefrom to establish and maintain a plurality'of annular electrical arcs substantially .at said intake ports each forming a zone through which a current of gas is required to flow in its passage through said conduit.

8. A nitrogen fixation apparatus comprising an absorption element a conduit through which a flow of gas to said absorbing element is adapted to be maintained and having a plurality of gas intake ports, an annular electrode for each of said intake ports, an electrode independently movable to and from each of said annular electrodes and insulated. therefrom to establish and maintain a plurality ofannular electrical arcs substantially at said intake ports each forming azone through which a current of gas is required to flow in its passage through said conduit, and means to enable said respective arcs to be observed.

' In testimony whereof I have aflixed my signature.

CHARLES H. BUETTNER. 

